This paper gives a theoretical analysis of the economic load dispatch problem by taking a three unit thermal system as the reference. Load allocation to each unit is determined using analytical method keeping in mind that it serves the total system load and satisfies the generation constraints. A MATLAB program is developed which gives the load allocation as output when the system load is varied step by step. Results are shown with the help of both tables and graphs. In the second phase system is again analyzed using a fuzzy controller and a comparative analysis is done in terms of the fuel costs obtained from conventional method and the fuzzy controller. The whole analysis is done without considering the transmission losses.